The present invention relates to a full automatic total inspection system suitable for assuring the total members of an implosion-protected cathode-ray tube by measuring and inspecting the performance of implosion-protection of the total members of the product by a nondestructive test.
Most of the cathode-ray tubes which are now in practical use are provided with implosion-protecting means.
FIG. 2 is a side elevational view of an implosion-protected cathode-ray tube. The reference numeral 1 represents a tension band for implosion-protection, 2 a welded part (nugget of weld) of a welded end of the tension band, 3 a reinforcement plate inserted between the tension band and a bulb, 4 a mounting lug, and 5 a glass panel all.
Although the mounting lug does not necessarily have a direct relation to the performance of implosion-protection (nevertheless, whether the mounting lugs are at the right positions or not are important to the user), the positional accuracy and the tension of the tension band for implosionprotection, the positional accuracy and the diameter of the nugget of weld of the welded part of the band, whether or not the mounting lug and the reinforcement plate are mounted and the positional accuracy thereof, and the thickness of the glass panel all have relations to the performance of implosionprotection of a cathode ray tube. However, because the measurement of these items by measuring apparatus is difficult, generally manually they are and visually inspected and some of them are statistically examined by sampling destructive tests.
That is, since an appropriate measuring method (e.g., a method for nondestructive measurement of the tension of a tension band for implosion-protection) has not been developed, or in consideration of the cost and the like of the measuring apparatus and controlling apparatus, a known impact test has conventionally been carried out as a test for assuring and confirming the safety to a person (the performance of implosion-protection). Since this is a kind of a destructive test, it is not adaptable to all the members of a product, and a process of statistically assuring all the members of the product in the population by the results of a test on a typical sample which is extracted from a population and the results of a substitutional character assurance test for assuring the performance of implosion-protection (implosion-protection performance test) on the sample has been adopted. However, as the requirements of general customers for the quality, and
the safety of a product increases, the assurance system which depends upon sampling tests in the statistic method has become unsatisfactory.
One of the known tests of this kind is disclosed in Japanese Patent Application Laid-Open No. 191933/1982.